Lookin good R@nSiD,
As a suggestion only, maybe add a 2nd light to slighly right of front to help bring out some of the pen colors a little more and it might also add an interesting sheen to the glass material (no need to have it cast shadows - it's more to give the impression of reflected/ambient light).
I love lookin at other artist's renders, gives me loads of ideas to try.
"If you think you can or if you think you can't....... you're right!"
- Henry Ford.
KickarZ Studios